Rattling noise Mercuiser 5.7

[DanielR]

I was experiencing rattling noise coming from 5.7 mercruiser engine.
The sound would be noticeable over 3500rpms and remain all the way up through the rpm range independent of the range or speed. I was thinking it maybe was the shield that rattled because of the loose bolts, i have removed it but noise continued.
Sound was very similar to the loose chain rattle. No knocking no misfiring.
To narrow down the source of noise I popped the engine cover and had someone peak around but the sound was coming from all round.
Any suggestion?

Thank You,
Daniel

 

[180shabah]

Re: Rattling noise Mercuiser 5.7 now water in the cylinder

Re: Rattling noise Mercuiser 5.7 now water in the cylinder

Rattling sounds like you were running lean.

Time for compression and/or leakdown test.

 

[HT32BSX115]

Re: Rattling noise Mercuiser 5.7 now water in the cylinder

Re: Rattling noise Mercuiser 5.7 now water in the cylinder

Rattling sounds like you were running lean.

Yes........... and possibly advanced timing might have caused detonation

 

[John Evans]

Re: Rattling noise Mercuiser 5.7

http://forums.iboats.com/showthread.php?t=209972&highlight=John+Evans

Mine sounded like cans in the compartment. I think it was a fuel/water filter and e-10 problem.

 

[180shabah]

Re: Rattling noise Mercuiser 5.7

Yup, water in the fuel will lean it out...

 

[Bondo]

Re: Rattling noise Mercuiser 5.7

Ayuh,.... Water in the fuel filter will definitely deliver Detonation, Big Time....

I'm just finishin' up a 350 Mag that dropped the #4 exhaust seat....
Doin' a 350 Efi now that dropped #7 exhaust seat....
All because of water in the Fuel Filter...